Energy efficiency (SEPR, ecodesign)
Also known as: SEPR, seasonal efficiency, ecodesign
Short definitionThe amount of cooling obtained for the electricity consumed. It is measured by COP for a single operating point and by SEPR for the weather of a whole year; the ecodesign regulation sets the minimum values.
Comparing two quotations on price alone is misleading, because over the life of the room several times the price of the equipment is paid in electricity. COP is an instantaneous ratio: a unit that draws 3 kW and delivers 7.5 kW of cooling has a COP of 2.5. SEPR divides annual cooling by annual consumption and counts part load too. EU Regulation 2015/1095 asks condensing units for a minimum of around 2.5 at medium temperature and 1.6 at low temperature.
Consumption is moved most by the evaporating and condensing temperatures; if the first rises by 1 K or the second falls by 1 K, the bill eases by 2–3%. Large-surface condensers and evaporators, EC fans, inverters, electronic expansion valves and floating head pressure are specified for that reason. In operation a frosted evaporator, a dusty condenser, undercharge and a worn door gasket can take 20–30% off the efficiency of a good unit. Panel thickness also sets the load.